Glass article and production method for glass article

ABSTRACT

The glass article has a three-dimensional shape. The glass article contains a first surface and at least one second surface opposite to the first surface, and contains a bent part in at least one place of the first surface or the second surface.

TECHNICAL FIELD

The present invention relates to a glass article and a method forproducing a glass article.

BACKGROUND ART

In recent years, in transportation devices such as automobiles, trains,ships, and aircrafts, for the purpose of protecting an interior memberand enhancing its appearance, a thin sheet-like cover glass is arrangedon the front surface of the interior member in some cases. Examples ofthe interior members of the transportation devices include instrumentpanels, head-up displays (HUD), dashboards, center consoles, shiftknobs, and the like.

The cover glass to be used in such an interior member of atransportation device has been required to possess various advantageousproperties as compared with the cover glass for usual use applications,i.e., the cover glass to be used in mobile phones, personal computers,televisions, or the like.

For example, the cover glass to be mounted on a transportation device isstrongly desired to achieve unity with a design effectively using aspace or a design pursuing comfortability in order to realize a highdesignability, a luxurious feel, and followability to interior design ofthe transportation device. However, it is difficult to realize suchproperties required for the cover glass for the interior member by aconventionally known planar glass or a simple three-dimensionally shapedglass.

Incidentally, Patent Document 1 discloses that, in a cover glass formobile electronic devices having a three-dimensional shape, surfaceroughness of the glass surface is made smaller than a predeterminedvalue.

PRIOR ART DOCUMENT Patent Document

Patent Document 1: WO2013/181208

SUMMARY OF THE INVENTION Problems that the Invention is to Solve

In addition, the cover glass for an interior member should satisfyvarious requirements such as environment-resistant properties, that is,high reliability even under severe temperature conditions of about −30°C. to +85° C., high luminance, wide viewing angle, antiglare properties,antireflection properties, and antifouling properties (antifinger-printproperties).

However, the cover glass of Patent Document 1 is invented on the premiseof mobile use applications and is not suitable for interior members oftransport devices, for example.

The present invention is made in consideration of the above problems andan object thereof is to provide a three-dimensionally shaped glasscapable of being used in various use applications.

Means for Solving the Problems

The above object of the invention is achieved by the followingconfigurations.

-   (1) A glass article having a three-dimensional shape, having a first    surface and at least one second surface opposite to the first    surface, and having a bent part in at least one place of the first    surface or the second surface.-   (2) The glass article according to (1), in which the first surface    and the second surface each have a bent part in at least one place    thereof.-   (3) The glass article according to (1) or (2), further having at    least one edge surface connecting the first surface and the second    surface,

in which the edge surface has an outline of a three-dimensional curve.

-   (4) The glass article according to any one of (1) to (3), in which    the bent part contains at least one site having an average radius of    curvature of 30 cm or less.-   (5) The glass article according to any one of (1) to (4), in which    the bent part contains at least one site having a Gaussian curvature    of not 0.-   (6) The glass article according to (5), in which the Gaussian    curvature is negative.-   (7) The glass article according to any one of (1) to (6), which is    mounted on a transportation device.-   (8) The glass article according to (7), which is used for an    interior member of the transportation device.-   (9) The glass article according to any one of (1) to (8), in which    at least a part of the first surface or the second surface of the    glass article is supported by a support member.-   (10) The glass article according to (9), in which at least one place    of the bent part is supported by the support member facing the bent    part.-   (11) The glass article according to (9) or (10), in which the    support member supports the bent part so that the bent part is    movable.-   (12) The glass article according to any one of (9) to (11), in which    the edge surface connecting the first surface and the second surface    is composed of a bent part edge surface connecting the bent part of    the first surface and the bent part of the second surface and

the bend part edge surface does not come into contact with the supportmember.

-   (13) The glass article according to any one of (9) to (12), in which    the support member has a Young's modulus of from 0.02 to 1.5 times    the Young's modulus of the glass article.-   (14) The glass article according to any one of (1) to (13), in which    at least one of the first surface and the second surface of the    glass article has been subjected to an etching treatment with    hydrofluoric acid.-   (15) The glass article according to any one of (1) to (13), further    containing an antiglare film provided on at least one of the first    surface and the second surface of the glass article.-   (16) The glass article according to any one of (14) to (15), in    which at least one of the first surface and the second surface of    the glass article has a gloss value of from 20 to 30.-   (17) The glass article according to any one of (14) to (16), in    which at least one of the first surface and the second surface of    the glass article has a haze value of 40% or less.-   (18) A method for producing a glass article, containing forming the    antiglare film by performing spray coating with a coating liquid    having antiglare properties, in the glass article described in any    one of (15) to (17).-   (19) The method for producing a glass article according to (18), in    which the coating liquid contains SiO₂ or a SiO₂ precursor.-   (20) The method for producing a glass article according to (18) or    (19), in which the antiglare film is formed by burning after the    spray coating is performed.-   (21) The method for producing a glass article according to (20), in    which the burning is performed by a thermal treatment at the time of    chemical strengthening of the glass article.-   (22) The glass article according to any one of (1) to (17), further    containing a low reflection film provided on at least one surface of    the glass article.-   (23) The glass article according to (22), in which the low    reflection film contains a film composed of a material having a high    refractive index and a film composed of a material having a low    refractive index stacking alternately.-   (24) The glass article according to any one of (1) to (17) and (22)    to (23), further containing an antifouling film provided on at least    one surface of the glass article.-   (25) The glass article according to any one of (1) to (17) and (22)    to (24), in which at least one surface of the glass article has a    coefficient of static friction of 1.0 or less.-   (26) The glass article according to any one of (1) to (17) and (22)    to (25), in which at least one surface of the glass article has a    coefficient of dynamic friction of 0.02 or less.-   (27) The glass article according to any one of (1) to (17) and (22)    to (26), having an arbitrary pattern printed on at least one surface    of the glass article.-   (28) The glass article according to (27), in which the pattern on    the bent part is printed by a pad printing method.-   (29) The glass article according to (27) or (28), in which at least    one surface of the glass article has a planar part connecting to the    bent part,

the bent part is printed by a pad printing method, and

the planar part is printed by a screen printing method.

-   (30) The glass article according to (27), in which the pattern on    the bent part is printed by a spray printing method.-   (31) The glass article according to (30), in which at least one    surface of the glass article has a planar part connecting to the    bent part and

the bent part and the planar part are both printed by a spray printingmethod.

-   (32) The glass article according to any one of (1) to (17) and (22)    to (31), in which the glass article has a total content of Li₂O and    Na₂O of 12 mol % or more.-   (33) The glass article according to (32), in which the glass article    contains 0.5 mol % or more of Li₂O.-   (34) The glass article according to (32), in which the glass article    contains 60 mol % or more of SiO, and 8 mol % or more of Al₂O₃.-   (35) The glass article according to any one of (1) to (17) and (22)    to (34), being chemically strengthened.-   (36) The glass article according to any one of (1) to (17) and (22)    to (35), further containing a resin film disposed on at least one    surface of the glass article.-   (37) A laminated glass article containing laminated one pair of the    glass articles described in any one of (1) to (17) and (22) to (36).-   (38) The laminated glass article according to (37), further    containing at least one sheet of a film having an optical function    or an antiscattering function disposed between one pair of the glass    articles, and containing a synthetic resin film having adhesiveness    disposed between the film and the glass article and between the    films.-   (39) A method for producing a laminated glass article containing    heating the glass article described in any one of (1) to (17)    and (22) to (36), at least one sheet of a film having an optical    function or an antiscattering function disposed between one pair of    the glass articles, and a synthetic resin film having adhesiveness    disposed between the films to a predetermined temperature and    subsequently pressurizing and crimping them,

in which the film has a shape that matches to the shape of the glassarticle before pressurizing and crimping.

Advantageous Effect of the Invention

The glass article of the present invention is a glass article having athree-dimensional shape, having a first surface and at least one secondsurface opposite to the first surface and having a bent part in at leastone place of the first surface and the second surface. Therefore, it issuitable for interior members of transportation devices, for example.Furthermore, the glass article of the present invention provides a glassarticle having an unknown attribute for various use applications thatcannot be realized by any conventional glass.

BRIEF DESCRIPTION OF DRAWINGS

[FIG. 1] (a) to (c) are cross-sectional views illustrating glassarticles.

[FIG. 2] (a) to (b) are cross-sectional views illustrating glassarticles.

[FIG. 3] (a) to (b) are cross-sectional views illustrating glassarticles.

[FIG. 4] it is a perspective view of the glass article of FIG. 2(a).

[FIG. 5] it is a diagram illustrating a step of performing spray coatingwith a coating liquid onto a glass article.

[FIG. 6] it is a diagram showing a relationship between haze values andgloss values of glass surfaces in the case of performing spray coatingwith a coating liquid.

[FIG. 7] it is a perspective view illustrating a glass article on whicha pattern is printed.

[FIG. 8] it is a cross-sectional view illustrating a laminated glassarticle.

[FIG. 9] (a) is a perspective view illustrating a state that a glassarticle is supported by a support member of a support shape 1 and (b) isa cross-sectional view thereof.

[FIG. 10] (a) is a perspective view illustrating a state that a glassarticle is supported by a support member of a support shape 2 and (b) isa cross-sectional view thereof.

[FIG. 11] (a) is a perspective view illustrating a state that a glassarticle is supported by a support member of a support shape 2 and (b) isa cross-sectional view thereof.

[FIG. 12] (a) is a perspective view illustrating a state that a glassarticle is supported by a support member of a support shape 3 and (b) isa cross-sectional view thereof.

[FIG. 13] (a) is a perspective view illustrating a state that a glassarticle is supported by a support member of a support shape 4 and (b) isa cross-sectional view thereof.

[FIG. 14] (a) is a perspective view illustrating a state that a glassarticle is supported by a support member of a support shape 5 and (b) isa cross-sectional view thereof.

[FIG. 15] (a) is a plan view for explaining a bent part strength testand (b) is a side view thereof.

[FIG. 16] (a) is a plan view for explaining a planar part strength testand (b) is a side view thereof.

[FIG. 17] it is a perspective view of a curved surface where Gaussiancurvature is positive.

[FIG. 18] it is a perspective view of a curved surface where Gaussiancurvature is negative.

[FIG. 19] it is a perspective view of a curved surface where Gaussiancurvature is 0.

[FIG. 20] it is a perspective view of a spherical surface.

[FIG. 21] it is a perspective view of a saddle surface.

MODE FOR CARRYING OUT THE INVENTION (Shape and Use Application)

The glass article of the present embodiment is a glass article having athree-dimensional shape and having a first surface and at least onesecond surface opposite to the first surface. Moreover, the glassarticle has a bent part in at least one place of the first surface andthe second surface. Here, a simple designation as a “surface” refers toeither the first surface or the second surface. Moreover, the “bentpart” means a portion where the surface is bent and average curvaturethereof is not zero.

Such a glass article can be used in various use applications and, inparticular, can be mounted on transportation devices such asautomobiles, trains, ships, and aircraft and be suitably used. When itis used for interior members of the transportation devices, such asinstrument panels, head-up displays (HUD), dashboards, center consoles,and shift knobs, a high designability, a luxurious feel and the like canbe imparted to the interior members and thus the interior design of thetransportation devices can be improved. Incidentally, in the presentembodiment, the first surface is also called an inner reverse surfaceand the second surface is also called an outer front surface. The innerreverse surface means a surface positioned inside an assembly includingthe glass article. The outer front surface means a surface positionedoutside the assembly. In the case where there is no assembly includingthe glass article, any one surface can be regarded as the inner reversesurface and a surface opposite to the inner reverse surface can beregarded as the outer front surface.

For example, (a) to (c) of FIG. 1 each illustrates glass 1 where theinner reverse surface 3 has a planar shape and at least one place of theouter front surface 5 has a bent part 7.

In the glass 1 of FIG. 1(a), a bent part 7 bending in such a direction(the upward direction in the figure) that it separates from the innerreverse surface 3 as approaching one edge side is provided on one edgepart (the left side part in the figure) of the outer front surface 5. Inthe glass 1 of FIG. 1(b), one pair of bent parts 7 bending in such adirection that they separate from the inner reverse surface 3 asapproaching both edge sides are provided on both edge parts of the outerfront surface 5. In the glass 1 of FIG. 1(c), bent parts 7 bending insuch a direction (the downward direction in the figure) that they comeclose to the inner reverse surface 3 as approaching both edge sides areprovided on both edge parts of the outer front surface 5.

In addition, (a) to (b) of FIG. 2 and (a) to (b) of FIG. 3 eachillustrate glass 1 having bent parts 7 in at least one place of theinner reverse surface 3 and of the outer front surface 5 and having edgesurfaces 9 that are sandwiched between the inner reverse surface 3 andouter front surface 5 and connect the both.

Also referring to FIG. 4, the glass 1 of FIG. 2(a) has one pair of bentparts 7 on both edge parts of the inner reverse surface 3, which bend insuch a direction that they separate from the outer front surface 5 asapproaching both edge sides. Furthermore, the glass 1 has another onepair of bent parts 7 on both edge parts of the outer front surface 5,which bend in such a direction that they come close to the inner reversesurface 3 as approaching both edge sides. Here, since the opposing bentpart 7 of the inner reverse surface 3 and bent part 7 of the outer frontsurface 5 have mutually homologizing shapes, that is, mutually almostparallel shapes, the inner reverse surface 3 and the outer front surface5 are made mutually almost parallel.

In the glass 1 of FIG. 2(b), the whole of the inner reverse surface 3 isformed of a bent part 7 bending in such a direction that it separatesfrom the outer front surface 5 as approaching both edge sides, and thewhole of the outer front surface 5 is formed of a bent part 7 bending insuch a direction that it comes close to the inner reverse surface 3 asapproaching both edge sides. Here, since the opposing bent part 7 of theinner reverse surface 3 and bent part 7 of the outer front surface 5have mutually homologizing shapes, that is, mutually almost parallelshapes, the inner reverse surface 3 and the outer front surface 5 aremade mutually almost parallel.

Each glass 1 of FIG. 3(a) and FIG. 3(b) has the same cross-sectionalshapes as those of FIG. 2(a) and FIG. 2(b), respectively. However, theconfigurations are different in that, in FIG. 2(a) and FIG. 2(b), thebent parts 7 extend toward both sides in a width direction of each glassbut, in FIG. 3(a) and FIG. 3(b), the bent parts 7 extend from the centerof the glass 1 to peripheral edge parts. Therefore, each glass 1 of FIG.3(a) and FIG. 3(b) has bottomed shape having an opening at the side ofthe inner reverse surface 3 (a downward side in the figure).

Incidentally, in the aforementioned FIG. 1 to FIG. 3, the position onwhich the bent part 7 is provided and its shape are illustrated bytaking a downward-side surface as the inner reverse surface 3 and takingan upward-side surface as the outer front surface 5. However, thedownward-side surface may be taken as the outer front surface 5 and theupward-side surface may be taken as the inner reverse surface 3. Forexample, in each glass 1 of (a) to (c) of FIG. 1, the configuration maybe one where the outer front surface 5 has a planar shape and at leastone place of the inner reverse surface 3 has a bent part 7, and a bentpart 7 may be provided in at least one place of the inner reversesurface 3 and the outer front surface 5.

Average curvature is a physical index representing how a surface isdeviated from a planar surface. Mathematical derivation of the averagecurvature is well known and is omitted in the present Description.Simply, the average curvature of a surface is determined as anintermediate value of the maximum value and the minimum value ofcurvature of a rotation body obtained by rotating a curved surfacecentering a normal vector of the curved surface at a certain point onthe surface. Moreover, the average radius of curvature of a surface isdetermined as the reciprocal of the average curvature. Specifically, forexample, as for a sphere having a radius of R, the average curvature atany point on the spherical surface thereof is 1/R. Furthermore, as for acylinder whose radius of the bottom surface is R, the maximum curvatureis 1/R and the minimum curvature is 0 at any point on the side surfacethereof so that the average curvature is 1/2R. Therefore, the value ofthe average curvature at a certain point on a surface is an importantparameter that represents a physical shape. The average curvature can bemeasured by a known arbitrary method.

Here, the average radius of curvature of the bent part 7 is preferably30 cm or less, more preferably 10 cm or less, still preferably 5 cm ofless, further preferably 3 cm or less, and most preferably 1 cm or less.In the case where the average radius of curvature is 30 cm or less, itcan suitably follow to a component having a complex shape. In otherwords, in the case where the average radius of curvature of the bentpart 7 is larger than 30 cm, there exists a component impossible tofollow.

Gaussian curvature is a physical index representing how a surface isdeviated from a planar surface. Mathematical derivation of the Gaussiancurvature is well known and is omitted in the present Description.Simply, the Gaussian curvature K of a surface is determined as a productof main curvatures k1 and k2 of the surface at a certain point on thesurface. That is, K=k1k2. For example, in the case where the Gaussiancurvature of a surface is positive, as illustrated in FIG. 17, thesurface has a bump or a peak at the point. In the case where theGaussian curvature is negative, as illustrated in FIG. 18, the surfacehas a saddle point. However, in the case where the Gaussian curvature is0, as illustrated in FIG. 19, the surface is equivalent to a flatsurface at the point. For example, specifically, as illustrated in FIG.20, a triangle depicted on a surface where the Gaussian curvature ispositive (e.g., a spherical surface) has a sum of interior angles(α+β+γ) of larger than 180°. As illustrated in FIG. 21, a triangledepicted on a surface where the Gaussian curvature is negative (e.g., asaddle surface) has a sum of interior angles (α+β+γ) of smaller than180°. Incidentally, a triangle depicted on a surface where the Gaussiancurvature is 0 (e.g., a side surface of a column) has a sum of interiorangles of equal to 180°. Therefore, the value of the Gaussian curvatureat a certain point on a surface is an important parameter thatrepresents a physical shape.

Here, the bent part 7 of the glass 1 can be made to have at least oneplace where the Gaussian curvature is not 0. In the case where theGaussian curvature of the bent part 7 is not 0, it can suitably followto a component having a complex shape. In other words, in the case wherethe Gaussian curvature of the bent part 7 is 0, there exists a componentimpossible to follow. Moreover, in the case where the Gaussian curvatureof the bent part 7 of the glass 1 is not 0, rigidity can be enhanced ascompared with the case where the glass curvature is 0. For example, inthe case of a glass having a surface where the Gaussian curvature is 0as illustrated in FIG. 19, the glass is easily bent in a certaindirection but, in the case of a glass where the Gaussian curvature isnot 0 as illustrated in FIG. 17 and FIG. 18, there is no direction inwhich the glass is easily bent.

The Gaussian curvature of the bent part 7 is preferably negative, morepreferably −0.1 or less, and further preferably −0.3 or less. In thecase where the Gaussian curvature of the bent part 7 is negative,particularly, it is suitable for utilization to interior membersrequiring a complex steric shape, such as a center console in transportdevices.

Furthermore, in the case where there is an edge surface 9 connecting theinner reverse surface 3 and the outer front surface 5 like the glasses 1of FIG. 2 and FIG. 3, the outline of the edge surface 9 is preferably athree-dimensional curve. Here, the “outline of the edge surface 9” meansone having a minimum path length among curves that are closed on theedge surface 9 and that necessarily intersect any curves on the surfaceof the glass 1, which connects an arbitrary point on the inner reversesurface 3 and an arbitrary point on the outer front surface 5. Thethree-dimensional curve herein means a curve that cannot be depicted ona planar surface. For example, the outline of the edge surface 9 in theglass of FIG. 4 is an outline 9 b indicated by a broken line.

(Production Method)

The method for producing the glass article according to the embodimentof the present invention is not particularly limited and those havingvarious compositions can be used. For example, it can be produced byblending various raw materials in appropriate amounts, heating andmelting them, subsequently homogenizing by defoaming or stirring,forming into a sheet by a well-known float process, down draw process(e.g., fusion process), press process or the like, cutting into adesired size after cooling slowly, subjecting the edge surface 9 topolishing, and providing a bent part 7 by an arbitrary method. Accordingto the order of the steps, since it is sufficient to cut a sheet-likeglass alone, the glass article can be efficiently produced. The order ofthe individual steps in the production method is not limited thereto.For example, it is also possible that the glass is formed into a sheet,and after annealing, a bent part 7 is provided by an arbitrary method,the glass is then cut into a desired size, and the edge surface 9 issubjected to polishing. Furthermore, after the bent part 7 is provided,the inner reverse surface 3 or the outer front surface 5 may be polishedin order to remove defects in the bent part 7.

(Composition and Chemical Strengthening)

Examples of the glass 1 to be used in the embodiment of the presentinvention include glass articles composed of soda lime silicate glass,aluminosilicate glass, borate glass, lithium aluminosilicate glass, orborosilicate glass.

Moreover, the glass 1 is enhanced its strength and scratch resistance byperforming chemical strengthening treatment to form a compressive stresslayer on the surface thereof. Chemical strengthening is a treatment offorming a compressive stress layer on a glass surface by exchanging analkali metal ion (typically Li ion or Na ion) having a smaller ionradius on the glass surface with another alkali metal ion (typically Kion) having a larger ion radius through ion exchange at a temperatureequal to or lower than the glass transition point. The chemicalstrengthening treatment can be performed by a conventionally knownmethod.

In order to perform such a chemical strengthening treatmentappropriately, the glass 1 preferably has a total content of Li₂O andNa₂O of 12 mol % or more. Further, since the glass transition point islowered and forming is facilitated as the content of Li₂O increases, theglass 1 preferably has a content of Li₂O of 0.5 mol % or more, morepreferably 1.0 mol % or more, and further preferably 2.0 mol % or more.Furthermore, for increasing surface compressive stress (CompressiveStress: CS) and depth of compressive stress layer (Depth of Layer: DOL),the glass 1 preferably contains 60 mol % or more of SiO₂ and 8 mol % ormore of Al₂O₃. Incidentally, the surface compressive stress of thechemically strengthened glass is preferably 300 MPa or more and thedepth of compressive stress layer is preferably 10 μm or more. Bycontrolling the surface compressive stress and depth of compressivestress layer of the chemically strengthened glass to these ranges,excellent strength and scratch resistance can be obtained.

As a specific composition of the glass article according to theembodiment of the present invention, there can be mentioned a glasscontaining, as a composition in terms of mol %, from 50 to 80% of SiO₂,from 0.1 to 25% of Al₂O₃, from 3 to 30% of Li₂O+Na₂O+K₂O, from 0 to 25%of MgO, from 0 to 25% of CaO, and from 0 to 5% of ZrO₂, but there is noparticular limitation. More specifically, the following glasscompositions may be mentioned. Incidentally, for example, “containingfrom 0 to 25% of MgO” means that MgO is not essential but may becontained up to 25%. The glass of (i) belongs to soda lime silicateglass and each glass of (ii) and (iii) belongs to aluminosilicate glass.

(i) A glass containing, as a composition in terms of mol %, from 63 to73% of SiO₂, from 0.1 to 5.2% of Al₂O₃, from 10 to 16% of Na₂O, from 0to 1.5% of K₂O, from 0 to 5.0% of Li₂O, from 5 to 13% of MgO, and from 4to 10% of CaO, as a composition in terms of mol %

(ii) A glass containing from 50 to 74% of SiO₂, from 1 to 10% of Al₂O₃,from 6 to 14% of Na₂O, from 3 to 11% of K₂O, from 0 to 5.0% of Li₂O,from 2 to 15% of MgO, from 0 to 6% of CaO, and from 0 to 5% of ZrO₂, thesum of contents of SiO, and Al₂O₃ being 75% or less, the sum of contentsof Na₂O and K₂O being from 12 to 25%, and the sum of contents of MgO andCaO being from 7 to 15%, as a composition in terms of mol %

(iii) A glass containing from 68 to 80% of SiO₂, from 4 to 10% of Al₂O₃,from 5 to 15% of Na₂O, from 0 to 1% of K₂O, from 0 to 5.0% of Li₂O, from4 to 15% of MgO, and from 0 to 1% of ZrO₂, as a composition in terms ofmol %

(iv) A glass containing from 67 to 75% of SiO₂, from 0 to 4% of Al₂O₃,from 7 to 15% of Na₂O, from 1 to 9% of K₂O, from 0 to 5.0% of Li₂O, from6 to 14% of MgO, and from 0 to 1.5% of ZrO₂, the sum of contents of SiO,and Al₂O₃ being from 71 to 75%, the sum of contents of Na₂O and K₂Obeing from 12 to 20%, and the content of CaO being less than 1% in thecase where it is contained, as a composition in terms of mol %

(Surface Treatment)

In the glass 1, when external light such as illumination or sunlight isprojected in a display surface, visibility is decreased by a reflectionimage. As countermeasures for suppressing the projection of the externallight, there are a method of forming roughness on the inner reversesurface 3 or the outer front surface 5 of the glass 1 by performing anetching treatment with hydrofluoric acid to achieve antiglareproperties, and a method of forming an antiglare film (antiglare layer)having roughness on the surface, on the inner reverse surface 3 or theouter front surface 5 of the glass 1. Accordingly, by making the glasssurface rough thereby diffusively reflecting the external light, thereflection image is made unclear.

In the case of performing the etching treatment with hydrofluoric acid,it is achieved by a method of immersion in a chemical liquid such as adipping method, a method of applying a chemical liquid such as a spincoating, a method of allowing a chemical liquid to flow, or the othermethod, similarly to a common wet etching treatment method. However, inthe case of the etching treatment with hydrofluoric acid, there is aconcern that nonuniformity remains on the inner reverse surface 3 or theouter front surface 5 and thus homogeneity is impaired. Particularly,since the glass 1 has a bent part 7 unlike the usual planar glass, thehydrofluoric acid solution may remain at the bent part 7, so thathomogenization of the etching treatment is not easy.

Therefore, instead of the etching treatment with hydrofluoric acid or incombination with the etching treatment with hydrofluoric acid, it ispreferable to perform a spray-coating treatment of the inner reversesurface 3 or the outer front surface 5 having a bent part 7 with acoating liquid having antiglare properties. For example, as in FIG. 5,in the case of the glass 1 where the outer front surface 5 has a bentpart 7, by controlling a nozzle 11 of a spraying device so as to followthe shape of the bent part 7 as illustrated by an arrow A, it ispossible to form a homogeneous antiglare film all over the whole outerfront surface 5.

Examples of the nozzle 11 to be used for spray coating include atwo-fluid nozzle, a one-fluid nozzle, and the like. The particlediameter of liquid drops of the coating liquid injected from the nozzleis usually from 0.1 to 100 μm and preferably from 1 to 50 μm. In thecase where the particle diameter of the liquid drops is 1 μm or more,roughness that exhibits a sufficient antiglare effect can be formedwithin a short period of time. In the case where the particle diameterof the liquid drops is 50 μm or less, appropriate roughness thatexhibits a sufficient antiglare effect is easily formed.

The particle diameter of the liquid drops can be appropriatelycontrolled by the kind of the nozzle 11, spraying pressure, amount ofliquid, and the like. For example, in the two-liquid nozzle, the liquiddrops decreases in size as the spraying pressure increases and theliquid drops increases in size as the amount of liquid increases. Theparticle diameter of the liquid drops is a Sauter mean particle diameterthat is measured by a laser measuring device.

FIG. 6 shows a relationship between haze values and gloss values of theglass surfaces in the case where various coating liquids are applied byspray coating. Incidentally, a black tape or the like is not attached tothe surface opposite to the surface on which the haze value and thegloss value are measured. The coating liquid contains an alkoxysilanehydrolytic condensate that is a main substance of forming a scatteredstructure and scattering particles that are a scattering aid and theratio and size of the scattering particles are different in individualcoating liquids.

According to the spray coating method, it is possible to change the hazevalue and the gloss value in wider ranges. The reason thereof isconsidered that, since the coating amount and material composition ofthe coating liquid can be freely changed, the roughness level necessaryfor obtaining required properties can be relatively easily formed.

The gloss value and the haze value are sometimes measured with attachinga black tape or the like to the surface opposite to the measuringsurface. The gloss value of the inner reverse surface 3 or the outerfront surface 5 of the glass 1 having an antiglare film is preferably 30or less, more preferably 28 or less, and further preferably 26 or less.In the case where the gloss value is 30 or less, the antiglare effectcan be sufficiently exhibited. The gloss value of the glass 1 ispreferably 20 or more and further preferably 21 or more. In the casewhere the gloss value is 20 or more, a decrease in contrast of an imagecan be suppressed.

The haze value of the inner reverse surface 3 or the outer front surface5 of the glass 1 having an antiglare film is preferably 40% or less,more preferably 35% or less, and further preferably 30% or less. In thecase where the haze value is 40% or less, a decrease in contrast can besufficiently suppressed. The haze value of the inner reverse surface 3or the outer front surface 5 of the glass 1 is preferably 15% or more,more preferably 16% or more, and further preferably 18% or more. In thecase where the haze value is 15% or more, the antiglare effect can besufficiently exhibited.

Here, the coating liquid to be used for spray coating preferablycontains SiO₂ or a SiO₂ precursor. Since the coating liquid containingSiO₂ or a SiO₂ precursor is excellent in temporal stability of theliquid and can easily form a rough shape by spray coating, it ispossible to control the gloss value of the inner reverse surface 3 orthe outer front surface 5 to a value of from 20 to 30 and also controlthe haze value thereof to 40% or less to thereby realize good antiglareproperties.

Moreover, since the reflectance of the antiglare film containing SiO₂ ora SiO₂ precursor becomes lower than the reflectance of the glass surfacein the case where the etching treatment with hydrofluoric acid isperformed, the spray coating treatment with the coating liquidcontaining SiO₂ or a SiO₂ precursor can achieve both of good antiglareproperties and good antireflection.

At the time of applying the coating liquid by the spray method, asubstrate is preferably heated at from 30 to 90° C. beforehand. In thecase where the temperature of the substrate is 30° C. or higher, aliquid medium (C) is promptly evaporated, so that a sufficient roughnesscan be easily formed. In the case where the temperature of the substrateis 90° C. or lower, close adhesiveness between the substrate and theantiglare film becomes good.

By heating the glass 1 at the time of spray coating with the coatingliquid, burning is performed simultaneously to application, or burningis performed by heating the antiglare film after application of thecoating liquid on the glass 1. Particularly in the latter case, it ispossible to omit the burning step by combining it with chemicalstrengthening step by performing it by the thermal treatment at the timeof the chemical strengthening of the glass 1. An antiglare layercontaining SiO₂ is formed by burning, and thereby chemical strength andmechanical strength of the inner reverse surface 3 or the outer frontsurface 5 is improved. Burning temperature is preferably from 200 to480° C. In the case where the burning temperature is 200° C. or higher,sufficient close adhesiveness can be secured and, in the case whereburning temperature is 480° C. or lower, crack generation in the filmcan be suppressed.

In the glass 1, in order to prevent the projection of an image caused bythe reflection of the external light resulting in a screen beingdifficult to be seen, it is preferable to reduce reflectance by forminga monolayer or multilayer low reflection film or antireflection film onthe inner reverse surface 3 or the outer front surface 5. As aconfiguration of the low reflection film at that time, use can be madeof one obtained by alternately stacking a film composed of a materialhaving a high refractive index and a film composed of a material havinga low refractive index.

Examples of the methods for forming such a low reflection film include awet coating method (a spray coating method, a spin coating method, a dipcoating method, a die coating method, a curtain coating method, a screencoating method, an inkjet method, a flow coating method, a gravurecoating method, a bar coating method, a flexo coating method, a slitcoating method, a roll coating method, etc.), a sputtering method (a DC(direct current) sputtering method, an AC (alternate current) sputteringmethod, an RF (high frequency) sputtering method, etc.), and the like.Particularly, in the case of containing a bent part 7 as in the case ofthe glass 1 of the present embodiment, it is preferable to adopt a spraycoating method. This is because it is possible to perform coating withfollowing the curved surface of the bent part 7.

Since the glass 1 may be touched by a human finger on use, stainsderived from finger print, sebum, sweat, and the like are prone toattach thereto. These stains are hard to remove when attached and areconspicuous depending on light and the like, so that there is a problemthat visibility and good appearance are impaired. In order to solve sucha problem, it is preferable to form an antifouling film(fingerprint-resistant film, antifinger-print film) on the glass 1. Forthe antifouling film, high water repellency and oil repellency arerequired in order to suppress the attachment of the stains and alsoabrasion resistance against wiping of the attached stains.

In order to satisfy these requirements, the antifouling film ispreferably one composed of a fluorine compound. Examples of the formingmethod of the antifouling film include a spray coating method. Forexhibiting the effect, the antifouling film is preferably provided as auppermost layer of the glass 1.

For the glass 1 which may be touched with a human finger on use, goodfinger slipperiness is required. The finger slipperiness of the glass 1can be evaluated by such indexes as a static friction coefficient and adynamic friction coefficient. The inner reverse surface 3 or the outerfront surface 5 of the glass 1 preferably has a static frictioncoefficient of 1.0 or less, more preferably 0.9 or less, and furtherpreferably 0.8 or less. In the case where the static frictioncoefficient is 1.0 or less, the finger slipperiness is good at the timewhen a human finger touches the inner reverse surface 3 or the outerfront surface 5 of the glass 1. Moreover, the inner reverse surface 3 orthe outer front surface 5 preferably has a dynamic friction coefficientof 0.02 or less, more preferably 0.015 or less, and further preferably0.01 or less. In the case where the dynamic friction coefficient is 0.02or less, the finger slipperiness is good at the time when a human fingertouches the inner reverse surface 3 or the outer front surface 5 of theglass 1. The static friction coefficient and the dynamic frictioncoefficient of the inner reverse surface 3 or the outer front surface 5of the glass 1 can be, for example, measured as follows. In a touchangle evaluation meter TL201Ts manufactured by Trinity-Lab Inc., apseudo-finger contactor manufactured by the same company is placed onthe inner reverse surface 3 or the outer front surface 5 of the glass 1in a state of applying a load of 30 g. This is moved on the innerreverse surface 3 or the outer front surface 5 at a rate of 10 mm/secondand the static friction coefficient and the dynamic friction coefficientare measured. A friction coefficient at the time when the contactorbegins moving from a stationary state is defined as the static frictioncoefficient and a friction coefficient at the time when the contactor ismoving is defined as the dynamic friction coefficient.

For satisfying such numerical ranges of the static friction coefficientand the dynamic friction coefficient, it is preferable to subject theinner reverse surface 3 or the outer front surface 5 to a treatment ofthe antifouling film or the like.

(Printing)

The glass 1 is not limited to clear one and, for the purpose ofenhancing aesthetic quality of the glass 1, displaying the function ofan interior member on which the glass 1 is mounted, or the like, may beone where an arbitrary pattern is printed on the inner reverse surface 3or on the outer front surface 5.

For example, in the case where the glass 1 is used as a cover glass of ashift knob of an automobile, usually, since the shift knob is composedof a complex curved surface, a bent part 7 having a complex curvature isprovided on the inner reverse surface 3 or the outer front surface 5 ofthe glass 1 that covers the shift knob. In this case, when it isintended to print an arbitrary pattern (e.g., a pattern indicating shiftpositions or the other pattern) on the bent part 7, it is suitable toperform printing by a pad printing method.

Here, the pad printing method is a method of printing by pressing a softpad (e.g., a silicone-made pad) having an ink pattern provided on thesurface thereof to an objective substrate to transfer the ink patternonto the substrate surface. This printing method is sometimes called a“pat” printing or a “tampo” printing. Since a relatively soft pad havinga good shape followability is used in the pad printing, it is preferableto perform printing by the pad printing method for the bent part 7 ofthe glass 1. Particularly, in the case where the Gaussian curvature atthe bent part 7 of the glass 1 is not zero, it is more preferable toperform printing by the pad printing method.

On the other hand, the printing method such as a screen printing methodis not suitable because the shape followability is not so high and thereis a possibility of dripping ink from the bent part 7. Incidentally, thescreen printing is a method of placing a printing material on a screenhaving openings and subsequently pressing and sliding a squeegee on thescreen to squeeze out the printing material from the openings of thescreen, thereby printing a pattern of the openings.

FIG. 7 illustrates the glass 1 where the inner reverse surface 3 has aplanar part 6 and a bent part 7 connecting to the both edge parts at thelongitudinal direction of the planar part 6 in which a printing has beenperformed on the both edge parts at the longitudinal direction of theinner reverse surface 3. The shape of the glass 1 is about the same asthe shape of the glass 1 of FIG. 2(a) and FIG. 4 mentioned above. InFIG. 7, the portion illustrated by polka-dot hatching is a printedportion. As above, in the case where the glass 1 has the planar part 6connecting to the bent part 7, when a linear pattern is printed by thepad printing method to the bent part 7 and the planar part 6, the outercircumference of the pad becomes an arc shape. Therefore, particularlyin the planar part 6, a boundary line B between the portion on which apattern is printed and the portion on which it is not printed isdifficult to make linear. Accordingly, by printing a pattern by the padprinting onto the bent part 7 and printing a pattern by the screenprinting onto the planar part 6, the boundary line B can be made linearand thus aesthetic quality can be enhanced.

Incidentally, the printing onto the planar part 6 is not limited to oneby the screen printing method and may be one by a rotary screen printingmethod, a letterpress printing method, an offset printing method, aspray printing method, or the like as long as it is one which theboundary line B between the portion on which a pattern is printed andthe portion on which it is not printed can be made linear. Moreover, itmay be a print by an electrostatic copying method, a thermal transfermethod, an inkjet method, or the like. Of these, in particular,according to the spray printing method, printing can be suitablyperformed onto the bent part 7 of the glass 1 similarly to the padprinting method. Moreover, also in the case of printing the linearpattern as illustrated in FIG. 7, the boundary line B can be made linearby masking the portion not to be printed and thus the aesthetic qualitycan be enhanced.

(Laminated Glass and Bilayer Glass)

The glass 1 may be a glass article having a film (so-called bilayerglass) where a resin film as a functional film is attached onto theinner reverse surface 3 or the outer front surface 5. Moreover, theglass 1 may be made a laminated glass article by laminating one pairthereof.

In the case of the laminated glass article, at least one sheet of a filmhaving an optical function or an antiscattering function may be disposedbetween one pair of the glasses 1. FIG. 8 illustrates a laminated glassarticle where an antiscattering film 13 and an optically functional film15 are disposed between one pair of the glasses 1. A synthetic resinfilm 17 having adhesiveness is disposed between the glass 1 and theantiscattering film 13, between the antiscattering film 13 and theoptically functional film 15 and between the optically functional film15 and the glass 1.

In such a laminated glass article, one pair of the glasses 1 arecombined by heating to a predetermined temperature, for example, 100° C.or higher and subsequently pressurizing them to achieve crimping. Here,in FIG. 8, the antiscattering film 13 and the optically functional film15 are represented as planar ones but it is preferable to form them intoa shape that matches to the shape of the glass 1, that is, a curvedshape almost parallel to the bent part 7 of the glass 1 in advancebefore the pressurization and crimping. Thereby, it becomes possible tocrimp the antiscattering film 13 and the optically functional film 15surely to one pair of the glasses 1. This method is particularlyeffective in the case where the antiscattering film 13 and the opticallyfunctional film 15 are composed of materials that are not easilydeformed.

(Strength and Support Member)

Particularly in the case of being used as an interior member of atransportation device, the aforementioned glass 1 (including a bilayerglass article and a laminated glass article) is required to haveespecially high strength in view of the use application. Accordingly, inorder to improve strength, the glass 1 is fixed to the interior memberin such a manner that at least a part of the inner reverse surface 3 orthe outer front surface 5 is supported by a support member provided onthe interior member or the like of the transportation device.

Hereinafter, in the case where a glass 1 where the inner reverse surface3 or the outer front surface 5 has the planar part 6 and the bent part 7connecting to the both edge parts at the longitudinal direction of theplanar part 6, as illustrated in (a) of FIG. 2, FIG. 4, FIG. 7, and thelike, is supported by a support member 20 of an interior member, thestrength of the glass 1 is investigated. As for the support member 20,there may be mentioned a polymer material such as polycarbonate,polyethylene terephthalate (PET), ABS, or a synthetic rubber, a metalmaterial such as aluminum or SUS, a ceramic material, and the like.

In such a glass 1, a part of the edge surface 9 connecting the innerreverse surface 3 and the outer front surface 5 is composed of a bentpart edge surface 9 a connecting the bent part 7 of the inner reversesurface 3 and the bent part 7 of the outer front surface 5. That is,there is a characteristic in that the bent parts 7 of the inner reversesurface 3 and the outer front surface 5 are provided so as to connect toa part of the edge surface 9 of the glass 1. FIG. 9 to FIG. 14illustrate those in which the shape of the support member 20 is changedto one of support shapes 1 to 5 to be mentioned later and the supportingconfiguration of the glass 1 by the support member 20 is changed.Incidentally, in FIG. 9 to FIG. 14, the longitudinal direction of theglass 1 is represented as X, the short direction is represented as Y,and the thickness direction is represented as Z.

(Support Shape 1)

FIG. 9 illustrates a support member 20 having a support surface 21almost parallel to the inner reverse surface 3. The support surface 21has a support planar surface 23 that supports facing the planar part 6of the inner reverse surface 3 and a support bent surface 25 thatsupports facing the bent part 7 of the inner reverse surface 3. Thesupport surface 21 extends to both sides in Y-direction more than theglass 1. The support bent surface 25 may be adhesively fixed to the bentpart 7 of the inner reverse surface 3 with an adhesive or may supportthe bent part 7 so as to be movable without adhesive fixing.

(Support Shape 2)

In the support member 20 of FIG. 10, a concave part 26 is provided on aportion excluding a side edge part at X-direction of the support bentsurface 25. Therefore, the support bent surface 25 only supports theside edge part at X-direction of the bent part 7 of the inner reversesurface 3. Incidentally, the support bent surface 25 and the bent part 7are adhesively fixed.

In the support member 20 of FIG. 11, the concave part 26 provided on thesupport bent surface 25 extends to the X-direction more than the supportmember 20 of FIG. 10 but the basic configuration is the same. Thesupport member 20 of FIG. 11 is different from the support member 20 ofFIG. 10 in view that the support bent surface 25 and the bent part 7 ofthe inner reverse surface 3 are not adhesively fixed and the supportbent surface 25 supports the bent part 7 so as to be movable.

(Support Shape 3)

The support surface 21 of the support member 20 of FIG. 12 has a supportconvex surface 27 that is protrusively provided from a side edge part atthe X-direction in a perpendicular direction to a normal line of thebent part 7 and supports the bent part edge surface 9 a. Theconfiguration other than the support convex surface 27 is the same asthat of the support member 20 of FIG. 9. The support convex surface 27may be adhesively fixed to the bent part edge surface 9 with an adhesiveor may support the bent part edge surface 9 so as to be movable withoutbeing adhesively fixed.

(Support Shape 4)

The support member 20 of FIG. 13 is different from the support member 20of FIG. 12 in view that the former has a side support surface 28 that isprotrusively provided from a side edge part at the Y-direction of thesupport bent surface 25 in a perpendicular direction to a normal line ofthe bent part 7 of the glass 1 and supports the side surface at theY-direction of the glass 1 from the Y-direction. The side supportsurface 28 may be adhesively fixed to the side surface at theY-direction of the glass 1 with an adhesive or may support the sidesurface at the Y-direction of the glass 1 so as to be movable withoutbeing adhesively fixed.

(Support Shape 5)

The support member 20 of FIG. 14 is different in configuration from thesupport member 20 of FIG. 13 in view that the support convex surface 27that supports the bent part edge surface 9 a is not provided. That is,the support member 20 of FIG. 14 is different in configuration from thesupport member 20 of FIG. 9 in view that the former has the side supportsurface 28.

For the glass 1 supported by the support member 20 of each of thesupport shapes 1 to 5, a strength test as mentioned below was performed.

(Bent Part Strength Test)

A bent part strength test was performed by dropping a sphere 30 from theupper side of the bent part 7 of the glass 1 while the lower surface 29of the support member 20 was completely restrained, as illustrated inFIG. 15. The strength test is a test according to simulation. The sphere30 is a rigid body and has a diameter of 165 mm, a mass of 6.8 kg, andan impact energy of 150 J. The center O of the sphere 30 at the time ofdropping was matched to the middle position Ym in Y-direction of theglass 1 and the boundary position Xb in X-direction between the planarpart 6 and the bent part 7 of the glass 1. The glass 1 has anX-direction size of 257 mm, a Y-direction size of 183 mm, and aZ-direction size of 6.7 mm. Also, the bent part 7 has an X-directionsize of 14.3 mm, a Y-direction size of 183 mm, a Z-direction size of 6.7mm, and an average radius of curvature of R23 mm. The material of thesupport member 20 was a polymer material (polycarbonate).

(Planar Part Strength Test)

A planar part strength test was performed by dropping a sphere 30 fromthe upper side of the planar part 6 of the glass 1 while the lowersurface 29 of the support member 20 was completely restrained, asillustrated in FIG. 16. The center O of the sphere 30 at the time ofdropping was matched to the middle position Ym in Y-direction of theglass 1 and the middle position Xm in X-direction of the glass 1. Theother conditions are the same as in the bent part strength test.

Table 1 shows results of the bent part strength test of the glass 1supported by the support member 20 of each of the support shapes 1 to 5.

TABLE 1 Maximum Stress in Y- Maximum stress of bent direction of Maximumstress of inner part edge bent part edge stress of outer reversePresence of surface surface front surface surface adhesive (MPa) (MPa)(MPa) (MPa) Support shape 1 present 600 45 2850 3520 (FIG. 9) Supportshape 1 absent 600 10 990 3620 (FIG. 9) Support shape 2 present 640 5002210 2430 (FIG. 10) Support shape 2 absent 800 30 1340 1730 (FIG. 11)Support shape 3 present 560 100 2840 3530 (FIG. 12) Support shape 3absent 560 40 1090 3600 (FIG. 12) Support shape 4 present 560 100 28503550 (FIG. 13) Support shape 4 absent 600 40 1000 3620 (FIG. 13) Supportshape 5 present 600 40 2860 3570 (FIG. 14) Support shape 5 absent 600 101110 3600 (FIG. 14)

Table 1 shows the presence or absence of the adhesive that adheres thesupport member 20 and the glass 1, maximum stress of the bent part edgesurface 9 a of the glass 1, stress in Y-direction of the bent part edgesurface 9 a, maximum stress of the outer front surface 5, and maximumstress of the inner reverse surface 3. Of the stress of each part, mostimportant for damage avoidance of the bent part 7 of the glass 1 is thestress of the bent part edge surface 9 a, particularly the stress inY-direction. This is because the edge surface of the glass 1 isgenerally a portion that has the lowest strength and is easily crackedin the glass 1 since the portion is subjected to cutting, polishing,chamfering, and the like, and a crack extends in the X-direction by thestress in Y-direction in many cases.

In any support shape, the maximum stress in Y-direction of the bent partedge surface 9 a remarkably decreases in the case of the absence of theadhesive as compared with the case of the presence of the adhesive. Thisis because, in the case of the absence of the adhesive, the bent part 7,the bent part edge surface 9 a, and the side surface in Y-direction ofthe glass 1 is movable and thus it is possible to disperse the stress atthe time of applying an impact load by the sphere 30.

When the support shape 1 having the support bent surface 25 facing thebent part 7 of the inner reverse surface 3 is compared with the supportshape 2 where the concave part 26 is provided on the support bentsurface 25, the maximum stress in Y-direction of the bent part edgesurface 9 a is 45 MPa (presence of the adhesive) and 10 MPa (absence ofthe adhesive) in the support shape 1, while it is 500 MPa (presence ofthe adhesive) and 30 MPa (absence of the adhesive) in the support shape2. Therefore, it is found that the stress decreases in the support shape1. As above, the bent part 7 is preferably supported by the support bentsurface 25 facing the bent part 7. Incidentally, the reason why the bentpart 7 is preferably supported by the support bent surface 25 is thatthe stress of the bent part edge surface 9 a can be reduced bysuppressing the deformation of the bent part 7.

When the support shape 1 having no support convex surface 27 is comparedwith the support shape 3 having the support convex surface 27, themaximum stress in Y-direction of the bent part edge surface 9 a is 45MPa (presence of the adhesive) and 10 MPa (absence of the adhesive) inthe support shape 1, while it is 100 MPa (presence of the adhesive) and40 MPa (absence of the adhesive) in the support shape 3. Therefore, itis found that the stress decreases in the support shape 1. Also, whenthe support shape 5 having no support convex surface 27 is compared withthe support shape 4 having the support convex surface 27, the maximumstress in Y-direction of the bent part edge surface 9 a is 40 MPa(presence of the adhesive) and 10 MPa (absence of the adhesive) in thesupport shape 5, while it is 100 MPa (presence of the adhesive) and 40MPa (absence of the adhesive) in the support shape 4. Therefore, it isfound that the stress decreases in the support shape 5. As above, thebent part edge surface 9 a is preferably configured so that the supportconvex surface 27 does not come into contact therewith. The reason whythe bent part edge surface 9 a is preferably not supported by thesupport convex surface 27 is that the stress in Y-direction can bereduced by securing the degree of freedom in the deformation of the bentpart 7.

When the support shape 1 having no side support surface 28 is comparedwith the support shape 5 having the side support surface 28, the maximumstress in Y-direction of the bent part edge surface 9 a is 40 MPa(presence of the adhesive) and 10 MPa (absence of the adhesive) in thesupport shape 5, while it is 45 MPa (presence of the adhesive) and 10MPa (absence of the adhesive) in the support shape 1. It is found thatthe numerical values almost do not change. Also, when the support shape3 having no side support surface 28 is compared with the support shape 5having the side support surface 28, the maximum stress in Y-direction ofthe bent part edge surface 9 a is 100 MPa (presence of the adhesive) and40 MPa (absence of the adhesive) in the support shape 4, while it is 100MPa (presence of the adhesive) and 40 MPa (absence of the adhesive) inthe support shape 3. The numerical values are equal. As above, the sidesupport surface 28 does not contribute the improvement in the strengthof the bent part 7 of the glass 1 but may be provided for positioning inthe Y-direction of the glass 1.

Table 2 shows results of the planar part strength test of the glass 1supported by the support member 20 of the support shape 1.

TABLE 2 Maximum Stress in Y- Maximum stress of bent direction of Maximumstress of inner part edge bent part edge stress of outer reversePresence of surface surface front surface surface adhesive (MPa) (MPa)(MPa) (MPa) Support shape 1 present — — 970 910 (FIG. 9)

From Table 2, it is found that large stress is not generated on the bentpart edge surface 9 a in the case where impact is imparted to the planarpart.

Incidentally, the material of the support member 20 is not limited tothe polymer material (polycarbonate) and any material may be applied aslong as it has the Young's modulus of the support member 20 is from 0.02to 1.5 times the Young's modulus of the glass 1. In the case where theYoung's modulus of the support member 20 is 0.02 times the Young'smodulus of the glass 1 or more, the stress of the bent part edge surface9 a decreases and, in the case where it is 1.5 times or less, the stressof the outer front surface 5 and the inner reverse surface 3 decreases.

The present application is based on Japanese Patent Application No.2014-101775 filed on May 15, 2014, and the contents are incorporatedherein by reference.

DESCRIPTION OF REFERENCE NUMERALS AND SIGNS

-   1 Glass-   3 Inner reverse surface (first surface)-   5 Outer front surface (second surface)-   6 Planar part-   7 Bent part-   9 Edge surface-   9 a Bent part edge surface-   9 b Outline-   11 Nozzle-   13 Antiscattering film-   15 Optically functional film-   17 Synthetic resin film-   20 Support member-   21 Support surface-   23 Support planar surface-   25 Support bent surface-   27 Support convex surface-   28 Side support surface-   29 Lower surface-   30 Sphere

1-39 (canceled)
 40. An interior member for transportation device,comprising: a glass having a bent part having a first surface and asecond surface, wherein the second surface of the glass has a staticfriction coefficient of 1.0 or less when the static friction coefficientis measured by placing a pseudo-finger contactor on the second surfaceof the glass and moving the pseudo-finger contactor at a rate of 10min/second in a state of applying a load of 30 g.
 41. The interiormember according to claim 40, wherein the second surface of the glass ison an outer front surface side.
 42. The interior member according toclaim 40, wherein the glass is a laminated glass comprising two or moresheets of glass and a resin film between the sheets of glass.
 43. Theinterior member according to claim 40, wherein the bent part contains atleast one site having an average radius of curvature of 30 cm or less.44. The interior member according to claim 40, wherein the bent partcontains at least one site having a Gaussian curvature of not
 0. 45. Theinterior member according to claim 44, wherein the Gaussian curvature isnegative.
 46. The interior member according to claim 40, wherein thesecond surface of the glass has a roughness on the surface.
 47. Theinterior member according to claim 46, wherein the roughness has anantiglare property.
 48. The interior member according to claim 40,wherein the first surface or the second surface of the glass comprises alow reflection film.
 49. The interior member according to claim 40,wherein the second surface of the glass comprises a antifouling film.50. The interior member according to claim 49, wherein the antifoulingfilm comprises a fluorine compound.
 51. The interior member according toclaim 40, wherein the glass has a haze value of 40% or less.
 52. Theinterior member according to claim 40, wherein the first surface of theglass has an arbitrary pattern printed.
 53. The interior memberaccording to claim 40, wherein the glass has a total content of Li₂O andNa₂O of 12 mol % or more.
 54. The interior member according to claim 40,wherein the glass contains 0.5 mol % or more of Li₂O.
 55. The interiormember according to claim 40, wherein the glass contains 60 mol % ormore of SiO₂ and 8 mol % or more of Al₂O₃.
 56. The interior memberaccording to claim 40, wherein the glass contains from 50 to 80 mol % ofSiO₂, from 0.1 to 25 mol % of Al₂O₃, and from 3 to 30 mol % ofLi₂O+Na₂O+K₂O.
 57. The interior member according to claim 40, whereinthe glass comprises a surface compressive stress layer.
 58. The interiormember according to claim 57, wherein the surface compressive stresslayer has a surface compressive stress of 300 MPa or more.
 59. Theinterior member according to claim 57, wherein the surface compressivestress layer has a depth of 10 μm or more.
 60. The interior memberaccording to claim 40, which is an instrument panel, a head-up display,a dashboard, a center console, or a shift knob.
 61. An interior assemblyfor transportation device, comprising: an interior member fortransportation device comprising a glass having a bent part having afirst surface and a second surface, wherein the second surface of theglass has a static friction coefficient of 1.0 or less when the staticfriction coefficient is measured by placing a pseudo-finger contactor onthe second surface of the glass and moving the pseudo-finger contactorat a rate of 10 mm/second in a state of applying a load of 30 g, and asupport member supporting the second surface of the glass.
 62. Theinterior assembly according to claim 61, wherein the second surface ofthe glass is on an outer front surface side.
 63. The interior assemblyaccording to claim 61, wherein the glass is a laminated glass comprisingtwo or more sheets of glass and a resin film between the sheets ofglass.
 64. The interior assembly according to claim 61, wherein the bentpart contains at least one site having a negative Gaussian curvature.65. The interior assembly according to claim 61, wherein the secondsurface of the glass has a roughness having an antiglare property, a lowreflection film, or a antifouling film.
 66. The interior assemblyaccording to claim 65, wherein the second surface of the glass comprisesan antifouling film, which comprises a fluorine compound.
 67. Theinterior assembly according to claim 61, wherein the support membersupports facing the bent part.
 68. The interior assembly according toclaim 61, wherein the support member is movable on the bent part. 69.The interior assembly according to claim 61, wherein the glass has anedge surface connecting the first surface and the second surface, andthe edge surface of the bent part does not come into contact with thesupport member.